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Centimeter Wavelengths

|< < Prev #3224 (March 25, 2026)

Title text: Yes, the cosmic microwave background is great, but what about the earthly microwave foreground?

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Explanation

Cosmic microwave background radiation is microwave radiation which permeates throughout the entire observable universe. It originated from light released during proton-electron recombination shortly after the Big Bang, which has since grown less energetic due to cosmological redshift, becoming microwave radiation which we see today. This radiation is not visible to the naked eye, but can be detected using specific radio instruments, including centimeter wavelength antennas, which are antennas designed to make detection in the 1-10 wavelength range; the Microwave band of radio waves.

In this comic, "Penzias & Wilson" refers to American astronomers and physicists Arno Allan Penzias and Robert Woodrow Wilson who, in 1978, were awarded the Nobel Prize in Physics "for their discovery of cosmic microwave background radiation". The story of their discovery was that during routine experiments with the Holmdel Horn Antenna, a centimeter wavelength antenna, Penzias and Wilson discovered that they were detecting a static background noise that they could not explain. After "debugging" the antenna and removing all potential sources of noise, they found that this background noise was still present, leading to their accidental discovery of the cosmic microwave background radiation.

On the other hand, Wi-Fi networks also transmit the signal using electromagnetic waves at around similar wavelengths. The common frequency bands currently used are 2.4 GHz and 5 GHz, and 6 GHz is seeing more use recently. The three ranges would roughly correspond to wavelengths of 12.5cm (4.92in), 6cm (2.36in), and 5cm (1.97in) respectively.

This comic is alluding to the fact that Penzias and Wilson are the only people who have won a Nobel prize from trying to debug a centimeter wavelength antenna, due to their accidental discovery of the cosmic microwave background radiation. On the other hand, people working in the IT sector may be spending even more time troubleshooting issues related to Wi-Fi connectivity on their site. Less technically capable workers may need extra support to properly setup up their workflow, while too capable ones could also risk breaking things in more profound ways...

Transcript

[A scatter plot graph with the Y axis of "time spent debugging centimeter-wavelength antennas" and X axis of "Nobel prizes awarded as a result". The X axis has the numbers 0 and 1 marked, while the Y axis has no numbers marked. Many dots arranged vertically appear at 0 on the X axis (zero Nobel prizes), collectively labeled as "I.T. people troubleshooting WiFi issues". A single dot appears at 1 on the X axis, vertically about 1/3 of the height of the graph up, labeled "Penzias & Wilson".]

[Caption below the panel:]

I just think the other people working in the field deserve at least a little recognition.

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